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1.
Zhonghua Yi Xue Za Zhi ; 104(17): 1514-1520, 2024 May 07.
Artigo em Chinês | MEDLINE | ID: mdl-38706059

RESUMO

Objective: To explore the effect and investigate the molecular mechanism of different concentrations of total tanshinones alone and in combination with tyrosine kinase inhibitors (TKIs) on the proliferation inhibition and apoptosis of human myeloid leukemia cell lines. Methods: K562 and Kasumi-1 cell lines were purchased from the Shanghai Cell Bank of the Chinese Academy of Sciences, and the TKIs-resistant strain K562/T315I cell line was constructed in Molecular Medicine Research Center, Beijing Lu Daopei Institute of Hematology. Logarithmic growth phase cells were taken and divided into intervention groups with total tanshinone of 0, 2.19, 4.38, 8.75, 17.50 and 35.00 µg/ml intervention groups, which were inoculated in 96-well plates at a density of 1×104 cells/well and exposed to the drug for 24 h, and a control group treated with dimethyl sulfoxide was also set up simultaneously. All experiments were repeated independently 3-5 times. The proliferative activity of the cells was assessed using the CCK-8 assay, the apoptotic rates were measured by flow cytometry, and the expression levels of apoptosis-regulating proteins Bcl-2 and Bax were analyzed by Western blotting. The cell lines treated and untreated with total tanshinone were subjected to transcriptome sequencing and gene set enrichment analysis to identify differentially expressed genes. Results: The half-inhibitory concentration (IC50) values of 8.75 µg/ml total tanshinone at 24 h for K562, K562/T315I and Kasumi-1 cells were (4.11±0.02), (4.95±0.04) and (3.98±0.01) µg/ml, respectively. When combined with 0.25 µmol/L imatinib, 8.75 µg/ml total tanshinone could enhance the induction of apoptosis effects on K562 and K562/T315I cell lines. After being treated with 4.38, 8.75, and 17.50 µg/ml of total tanshinone for 24 h, compared with the control group, total tanshinone upregulated the expression level of Bax protein, downregulated the expression level of Bcl-2 protein, and decreased the Bcl-2/Bax ratio (all P<0.05). Total tanshinone inhibited the proliferation-related signaling pathway and DNA damage repair pathway of myeloid leukemia cell lines, and activated the signaling pathway that induces apoptosis in leukemia cells. Conclusion: Different concentrations of total tanshinoneinhibites proliferation and promote apoptosis in K562, Kasumi-1 and TKIs-resistant K562/T315I cell lines, and further enhance the anti-leukemic effect when combined with TKIs.


Assuntos
Abietanos , Apoptose , Proliferação de Células , Leucemia Mieloide , Inibidores de Proteínas Quinases , Humanos , Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células K562 , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
2.
Zhonghua Yi Xue Za Zhi ; 103(18): 1386-1392, 2023 May 16.
Artigo em Chinês | MEDLINE | ID: mdl-37150691

RESUMO

Objective: To explore the construction of a machine learning model based on unbalanced data to predict the progression of non-nephrotic membranous nephropathy. Methods: The clinical and pathological data of patients diagnosed with non-nephrotic membranous nephropathy by renal biopsy in Shanxi People's Hospital from January 2018 to December 2021 were retrospectively analyzed.The prediction models were constructed based on logistic regression, support vector machine (SVM) and light gradient boosting machine (lightGBM), respectively. The mixed sampling technology was used to process the unbalanced data, and the area under the receiver operating characteristic curve (AUC) was used to evaluate the predictive performance of the models. Finally, Shapley additive explanation (SHAP) was used to interpret the results of the optimal prediction model. Results: A total of 148 patients were included in the study, including 84 males and 64 females, with a mean age of (47.2±12.5) years. The follow-up time [M(Q1, Q3)] was 14(7, 20) months. Twenty-three patients (15.5%) achieved the renal end-point event in the study. The SVM model had the highest AUC (0.868, 95%CI: 0.813-0.925), followed by logistic regression (AUC=0.865, 95%CI: 0.755-0.899) and lightGBM (AUC=0.791, 95%CI: 0.690-0.882). The feature recursive elimination cross validation (RFECV) method based on random forest (RF) and the SHAP plot based on the SVM model showed that immunohistochemistry IgG, total protein (TP), anti-phospholipase A2 receptor (anti-PLA2R), blood chloride and D-Dimer were risk factors affecting the progress of non-nephrotic membranous nephropathy. Moreover, patients with high immunohistochemistry IgG, anti-PLA2R and D-Dimer had an increased risk of achieving the renal end-point event. Conclusion: The SVM model established in this study can effectively predict the progress of non-nephrotic membranous nephropathy, and provide a new method for the early identification of high-risk patients and precision therapy.


Assuntos
Glomerulonefrite Membranosa , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Prognóstico , Glomerulonefrite Membranosa/tratamento farmacológico , Estudos Retrospectivos , Rim/patologia , Imunoglobulina G/uso terapêutico
3.
Zhonghua Yi Xue Za Zhi ; 103(18): 1401-1409, 2023 May 16.
Artigo em Chinês | MEDLINE | ID: mdl-37150693

RESUMO

Objective: To construct Bayesian network (BN) models to explore the factors related to glomerular injury (GI) and tubular injury (TI). Methods: A cross-sectional study was carried out. From April to November 2019, Shanxi Provincial People's Hospital performed an opportunistic screening for chronic kidney disease in 10 counties of Shanxi Province. The general data and laboratory results of blood and urine samples were collected. Chi-square test and logistic regression were used to explore the related factors of GI and TI, which were included in the construction of BN models with max-min hill-climbing (MMHC) algorithm. Results: A total of 12 269 participants were included, there were 5 198 males and 7 071 females, with a median age of 58 (40-91) years. The prevalence of GI and TI was 12.7% (1 561/12 269) and 11.6% (1 425/12 269), respectively. The BN model consisted of 8 nodes and 10 edges for GI, and 11 nodes and 17 edges for TI, respectively. BN models showed that age and glycated hemoglobin were direct related factors for GI, while gender and fasting blood glucose were indirect related factors for GI. Age, gender, fasting blood glucose and glycosylated hemoglobin were direct related factors for TI. Additionally, the area under the receiver operating characteristic curve (AUC) was 0.761 (95%CI: 0.746-0.777) and 0.753 (95%CI: 0.736-0.769) for GI and TI BN models, respectively. Conclusions: BN models allow for identifying the complex network relationships among the factors related to GI and TI. Meanwhile, Bayesian risk reasoning can provide reference value for the clinical prevention of GI and TI.


Assuntos
Glicemia , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Teorema de Bayes , Hemoglobinas Glicadas , Curva ROC
5.
Zhonghua Wei Chang Wai Ke Za Zhi ; 24(5): 433-439, 2021 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-34000773

RESUMO

Objective: At present, though the laparoscopic delta-shaped anastomosis and overlapping delta-shaped anastomosis have been gradually applied to complete laparoscopic radical resection of left hemicolon cancer, the comparative evaluation of their efficacy has not been mentioned in the published literatures. This study aims to explore the safety, feasibility and short-term efficacy of overlapping delta-shaped anastomosis (ODA) in totally laparoscopic left hemicolectomy. Methods: A retrospective cohort study was performed. The clinical and pathological data of patients who underwent totally laparoscopic left hemicolectomy at Department of Colorectal Surgery, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from May 2017 to October 2020 were retrospectively analyzed. The case inclusion criteria were as follows: (1) age of 18-75 years; (2) body mass index (BMI) of 18.5-30 kg/m(2); (3) descending colonic and proximal sigmoid colonic adenocarcinoma was confirmed by preoperative colonoscopy and pathology. The exclusion criteria: (1) multiple primary colorectal cancers; (2) uncontrolled or poorly controlled diabetes mellitus, immune system diseases, or hematological diseases; (3) severe intestinal obstruction; (4) left transverse colonic or splenic flexure colonic adenocarcinoma; (5) distant metastasis of liver, lung and other viscera determined by enhanced computed tomography in the chest, abdomen and pelvis. According to the above criteria, a total of 115 patients with left hemicolon cancer were enrolled. All the patients underwent totally laparoscopic left hemicolectomy. Patients who underwent laparoscopic traditional delta-shaped anastomosis were selected as the control group. Patients who underwent laparoscopic ODA were selected as the ODA group. Effects of these two laparoscopic reconstruction methods on postoperative recovery and perioperative complications were analyzed and compared. Results: A total of 60 patients were enrolled in the ODA group, including 32 males and 28 females, with mean age of (57.3±10.4) years and body mass index (BMI) of (25.0±3.1) kg/m(2). While mean 55 patients were enrolled in the control group, including 31 males and 24 females, with mean age of (56.7±9.9) years and BMI of (24.4±2.9) kg/m(2). There was no statistically significant differences between the two groups in gender, age, BMI, American Society of Anesthesiologist (ASA) classification, TNM staging, preoperative abdominal surgery history, neoadjuvant chemotherapy and nutritional status (levels of hemoglobin, lymphocyte count, prealbumin, and albumin) (all P>0.05). All the patients in both groups received R0 resection without conversion to open laparotomy or conversion to extra-abdominal anastomosis. The digestive tract reconstruction time of the ODA group was significantly shorter than that of the control group [(15.1±1.7) minutes vs. (15.9±2.4) minutes, t=-2.053, P=0.042]. There were no statistically significant differences in the total operation time, intraoperative blood loss, length of skin incision, tumor size, proximal and distal margins, harvested lymph nodes, postoperative first ambulatory time, and postoperative hospital stay (all P>0.05). However, the time to the first flatus and the first defecation in the ODA group was significantly shorter as compared to control group [(1.5±0.5) days vs. (1.7±0.5) days, t=-2.028, P=0.045; (3.1±0.6) days vs. (3.4±0.7) days, t=-2.095, P=0.039], indicating faster intestinal function recovery in patients with ODA. The morbidity of postoperative complication was 6.7% (4/60) in the ODA group and 7.3% (4/55) in the control group and no significant difference was found (χ(2)=0.016, P=0.898). Two cases of incision infection, 1 case of lung infection, and 1 case of intra-abdominal infection occurred in the ODA group, while 3 cases of lung infection and 1 case of intra-abdominal infection occurred in the control group. All these complications were resolved after conservative treatment, and no secondary operation was performed due to complications. Conclusion: Compared with the traditional delta-shaped anastomosis, ODA is associated with a faster recovery of postoperative intestinal function without increasing the morbidity of postoperative complications, and has the satisfactory short-term efficacy.


Assuntos
Colectomia , Laparoscopia , Adolescente , Adulto , Idoso , Anastomose Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Zhonghua Yi Xue Za Zhi ; 101(13): 926-933, 2021 Apr 06.
Artigo em Chinês | MEDLINE | ID: mdl-33789373

RESUMO

Objective: To classify and quantify IKZF1 mutant transcripts in B-cell acute lymphoblastic leukemia (B-ALL) by RNA sequencing (RNA-seq) and bioinformatics analysis. Methods: A cohort of 263 B-ALL cases was enrolled at Hebei Yanda Ludaopei Hospital from September 2018 to September 2020. An integrated bioinformatics pipeline was developed to adapt the classification and quantification of IKZF1 transcripts from RNA-seq and was applied to sequencing data of these cases. The IKZF1 mutant transcripts classified by RNA-seq analysis were compared with the qualitative reverse transcription PCR (RT-PCR). Results: IKZF1 mutant transcripts were identified in 53 B-ALL patients by RT-PCR and Sanger sequencing, among which IK6 and IK10 transcripts accounted for 67.9% (36/53) and 28.3% (15/53) respectively. Additionally, 2 patients were double positive for IK6 and IK10. RNA-seq analysis identified 51 patients with IKZF1 mutant transcripts. Compared with the RT-PCR result, the detection sensitivity and specificity of RNA-seq analysis reached 94.3% (50/53) and 99.5% (209/210), respectively. Among the 50 patients with IKZF1 mutant transcripts both in RNA-seq and RT-PCR analysis, the ratio of mutant transcripts to total IKZF1 transcripts in 6 patients was 0.14 (0.11, 0.35), which was significantly lower than that of the other 44 patients [0.88 (0.35, 0.97), Z=-3.945,P<0.001]. IKZF1 mutations mostly occurred in Ph+and Ph-like B-ALL, characterized by abnormal JAK-STAT pathway, and B-ALL with PAX5 translocation. Conclusions: Through the optimized bioinformatics analysis process, RNA-seq data can be used to classify and quantitatively analyze IKZF1 transcripts in B-ALL. Furthermore, the relative expression of mutant IKZF1 transcripts was found to cluster into two groups, and IKZF1 mutation was found often accompanied with PAX5 translocations.


Assuntos
Fator de Transcrição Ikaros , Leucemia-Linfoma Linfoblástico de Células Precursoras , Linfócitos B/metabolismo , Humanos , Fator de Transcrição Ikaros/genética , Fator de Transcrição Ikaros/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico , Isoformas de Proteínas , Transcriptoma
7.
Zhonghua Yi Xue Za Zhi ; 100(43): 3443-3447, 2020 Nov 24.
Artigo em Chinês | MEDLINE | ID: mdl-33238676

RESUMO

Objective: To explore the application and discovery of genotyping, gene sequencing, and gene expression analysis in the determination of ABO blood group subtypes and antigen expression abnormalities in hematological malignancies patients. Methods: From June 2019 to May 2020, three clinical cases were found with forward and reverse ABO typing discrepancy or atypical serologic agglutination pattern in the laboratory and blood transfusion department of Hebei Yanda Ludaopei Hospital were selected. Sequence-specific primer PCR (PCR-SSP) and Sanger sequencing of ABO gene coding regions were performed to determine the ABO genotypes, and whole transcriptome sequencing was used to analyze ABO and FUT1 gene expression levels. Results: A 12-year-old female acute lymphoblastic leukemia patient was determined as O.01.02 and BA.04 sub-genotype, corresponding to the serological B(A) subtype, and her ABO gene expression was normal (354.80). A 41-year-old female acute myeloid leukemia patient was determined as A1.02 and B.01 genotype, corresponding to the serological A(1)B phenotype, and her ABO gene expression was significantly reduced (45.70). A 42-year-old male with myelodysplastic syndrome and myelofibrosis was determined as A1.02 and A2.05 sub-genotype, corresponding to the serological A(1) and A(2) phenotype, respectively, and his ABO expression was negative. FUT1 expression was in the normal range in all three cases. The clinical blood product infusion strategy was formulated according to the genotype and the corresponding immunological subtype, and no significant transfusion-related adverse reactions occurred. Conclusion: Blood group sub-genotypes or aberrant gene expression can lead to ambiguities in serological blood group determination in hematological malignancies patients. ABO genotyping and gene expression analysis can help in this scenario and escort blood product infusion safety.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Neoplasias Hematológicas , Sistema ABO de Grupos Sanguíneos/genética , Adulto , Alelos , Criança , Genótipo , Neoplasias Hematológicas/genética , Humanos , Masculino , Fenótipo
8.
Zhonghua Yi Xue Za Zhi ; 100(2): 141-145, 2020 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-31937055

RESUMO

Objective: To observe the effect of autophagy of tibial growth plate chondrocyte on apoptosis in chronic renal insufficiency (CRI) rats. Methods: Male 4-week-old SD rats were randomly divided into two groups: (1) Sham group: only the left ureter was exposed (n=10); (2) CRI group: the left ureter was ligated to cause CRI (n=10). The urine from all the rats was collected 6 weeks after the operation and the total protein content was measured. Then all the rats were sacrificed and the concentrations of creatinine and urea nitrogen in intracardiac blood were detected. The proximal tibia were fixed and decalcified to prepare histological sections, and the number of chondrocytes of column cells in the proliferative area of tibia growth plate was observed by saffron O staining. The expression rate of protein Light Chain-3, an autophagy marker of chondrocytes, was detected by immunofluorescence. The apoptosis rate of chondrocytes was detected by the method of TUNEL assay. The level of glycogenin-1, a glycogen formation marker of chondrocyte was detected by immunohistochemistry in chondrocytes. Results: The 24 h urine total protein was higher in CRI group [(163.5±11.3) mg vs (38.6±9.8) mg, t=25.620, P<0.001]. The levels of blood creatinine [(67.3±16.2) µmol/L vs (28.4±11.5) µmol/L, t=5.974, P<0.001] and urea nitrogen [(16.4±6.4) mmol/L vs (4.8±2.0) mmol/L, t=5.198, P<0.001] were higher in CRI group. The number of chondrocytes of column cells in the proliferating area of tibia growth plate was lower in CRI group (4.2±2.1 vs 9.1±3.8, t=3.109, P=0.006). The expression rate of LC-3 protein in chondrocytes of CRI group was lower [(27.2±12.6)% vs (51.4±18.2)%, t=3.457, P=0.003]. The level of glycogenin-1 of chondrocytes in CRI group increased significantly (6.1±2.5 vs 3.5±1.8, t=2.669, P=0.016). The apoptosis rate of chondrocytes in CRI group also increased [(17.2±4.8)% vs (5.1±3.4)%, t=6.505, P<0.001]. Conclusion: Malfunction of autophagy in tibial growth plate chondrocytes causes increased apoptosis rate in CRI rats, which might be caused by the failure of glycogen degradation in chondrocytes.


Assuntos
Autofagia , Insuficiência Renal Crônica , Animais , Apoptose , Condrócitos , Lâmina de Crescimento , Masculino , Ratos , Ratos Sprague-Dawley , Tíbia
9.
Zhonghua Yi Xue Za Zhi ; 99(46): 3645-3651, 2019 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-31826587

RESUMO

Objective: To observe the effect of primary cilia expression rate on Wnt/ß signaling pathway in tibial growth plate chondrocytes from chronic renal insufficiency (CRI) young rats. Methods: Male 2-week-old SD rats were randomly divided into two groups: (1) Sham group: only the left ureter was exposed (n=6); (2) CRI group: the left ureter was ligated (n=6). Rats were sacrificed 2 weeks after the operation and the primary cilia expression rate of growth plate chondrocytes and key protein ß-catenin in Wnt/ß signaling pathway were observed in histological section of tibia specimen. Chondrocytes isolated from growth plate in two groups were cultured in vitro to P3 generation. The primary cilia expression rate and the level of ß-catenin were measured. The primary cilia expression rate was detected by agonists and antagonists Wnt/ß signaling pathway in chondrocytes of CRI group. The level of ß-catenin was detected by using serum-free culture and chloral hydrate to intervene chondrocytes in CRI group. Results: The primary cilia expression rate of growth plate chondrocytes in histological section of tibia specimen in CRI group was higher than that in Sham group [(17.5±7.7)% vs (8.7±3.6)%, t=3.237, P=0.005], and the level of ß-catenin was higher in CRI group (5.1±0.7 vs 1.9±0.8, t=6.731, P<0.001). The primary cilia expression rate of growth plate chondrocytes cultured in vitro in CRI group was higher than that in Sham group [(20.9±8.1)% vs (11.8±4.7)%, t=3.073, P=0.007], and the level of ß-catenin was higher in CRI group (0.49±0.12 vs 0.25±0.11, t=3.297, P=0.011). There was no significant change in primary cilia expression rate after intervention by using Wnt/ß signaling agonists and antagonists to change the level of ß-catenin [agonists group: (21.3±7.6)%, control: (20.6±6.8)%, antagonists group: (22.4±6.2)%, F=0.173, P=0.842]. The level of ß-catenin was significantly changed after intervention by using serum-free culture, chloral hydrate to alter the primary cilia expression rate (serum-free culture group: 0.61±0.23, control: 0.39±0.24, chloral hydrate group: 0.15±0.11, F=6.476, P=0.012). There was a positive correlation between the level of ß-catenin and primary cilia expression rate. Conclusion: The primary cilia expression rate and the level of Wnt/ß signaling pathway were higher in tibial growth plate chondrocytes in CRI rats model, and primary cilia might have positive regulatory effects on the Wnt/ß signaling pathway.


Assuntos
Condrócitos , Insuficiência Renal Crônica , Envelhecimento , Animais , Células Cultivadas , Cílios , Lâmina de Crescimento , Masculino , Ratos , Ratos Sprague-Dawley , Tíbia , Via de Sinalização Wnt , beta Catenina
10.
Insect Mol Biol ; 28(4): 578-590, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30737848

RESUMO

The QM gene that encodes for the ribosomal protein L10 was firstly identified from human tumour cells as a tumour suppressor. In this study, a QM gene was identified in silkworm Bombyx mori (BmQM) and its immunomodulatory function was explored. BmQM messenger RNA (mRNA) and protein were highly expressed in the silk gland and fat body, and expressed in all stages of silkworm growth. After challenged with four different microorganisms, the expression levels of BmQM mRNA in fat body or haemocytes were significantly upregulated compared with the control. After knock-down of BmQM gene, the expressions of some immune genes (PGRPS6, Gloverin0, Lysozyme and Moricin) were affected, and the transcripts of prophenoloxidase1 and prophenoloxidase2 have different degrees of change. The phenoloxidase activity was significantly reduced when the purified recombinant BmQM protein was injected. Recombinant BmQM protein inhibited systemic melanization and suppressed prophenoloxidase activation stimulated by Micrococcus luteus, but it did not affect phenoloxidase activity. Far-western blotting assays showed that the BmQM protein interacted with silkworm BmJun protein, which negatively regulates AP-1 expression. Our results indicated that BmQM protein could affect some immune gene expression and negatively regulate the prophenoloxidase-activating system, and it may play an important role in regulation of the innate immunity in insects.


Assuntos
Bombyx/genética , Catecol Oxidase/genética , Precursores Enzimáticos/genética , Proteínas de Insetos/genética , Proteína Ribossômica L10/genética , Animais , Bombyx/enzimologia , Bombyx/crescimento & desenvolvimento , Bombyx/imunologia , Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Perfilação da Expressão Gênica , Imunidade Inata/genética , Proteínas de Insetos/metabolismo , Larva/enzimologia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/imunologia , Micrococcus luteus/fisiologia , Pupa/enzimologia , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/imunologia , Proteína Ribossômica L10/metabolismo
11.
Nanoscale ; 10(15): 7026-7032, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29611859

RESUMO

Tuning of molecular conductance in a liquid environment is a hot topic in molecular electronics. In this article, we explore a new concept where the Fermi level positions of the metallic ends are varied simply by modifying the electroactive salt concentration in solution. We rely on the electrochemical scanning tunneling microscope break junction method that allows the construction in solution of copper atomic contacts that can be then bridged by single molecules. The experimental conductance evolution is first confronted with an analytical formulation that allows the deduction of the molecule's LUMO position and electronic coupling factors. These parameters are in close agreement with those obtained by independent DFT calculations.

12.
RSC Adv ; 8(69): 39314-39320, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-35558061

RESUMO

B4C-based ceramic composites containing 0-2 vol% highly aligned graphene nanoplatelets (GNPs) are fabricated. The electromagnetic interference (EMI) shielding properties of the obtained composites are investigated at X-band (8.2-12.4 GHz) frequency range from room-temperature up to 800 °C. All composites exhibit outstanding EMI shielding properties with satisfactory frequency- and thermal-stability. The shielding effectiveness (SE) of GNP/B4C composites increases monotonically with increasing GNP loading. Superior room-temperature SE close to 40 dB is achieved with only 2 vol% GNPs and high SE around 35 dB still persists at 800 °C. Considering their relatively low density, GNP/B4C composites possess a high specific shielding effectiveness (SSE) of 16 dB cm3 g-1 which is among the highest values in reported ceramic-based shielding composites. Especially, the GNP/B4C composite with 2 vol% GNPs exhibits the highest SSE/t (SSE divided by thickness) values at temperatures above 200 °C for all reported shielding composites, indicating that GNP/B4C composites belong to the most promising high-temperature shielding composites. The excellent shielding properties of GNP/B4C composites arise mainly from the high electrical conductivity, high dielectric loss and the multiple reflections by the highly aligned and large-sized GNP layers.

13.
Apoptosis ; 22(4): 544-557, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28188387

RESUMO

Quercetin (3,3',4',5,7-pentahydroxyflavone, Qu) is a promising cancer chemo-preventive agent for various cancers because it inhibits disease progression and promotes apoptotic cell death. In our previous study, we demonstrated that Qu could evoke ER stress to enhance drug cytotoxicity in ovarian cancer (OC). However, Qu-induced ER stress in OC is still poorly understood. Here, we demonstrated that Qu evoked ER stress to involve in mitochondria apoptosis pathway via the p-STAT3/Bcl-2 axis in OC cell lines and in primary OC cells. Unexpectedly, inhibition of ER stress did not reverse Qu-induced cell death. Further functional studies revealed that Qu-induced ER stress could activate protective autophagy concomitantly by activating the p-STAT3/Bcl-2 axis in this process. Moreover, the autophagy scavenger 3-MA was shown to enhance Qu's anticancer effects in an ovarian cancer mice xenograft model. These findings revealed a novel role of ER stress as a "double edge sword" participating in Qu-induced apoptosis of OC and might provide a new angle to consider in clinical studies of biological modifiers that may circumvent drug resistance in patients by targeting protective autophagy pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Neoplasias/fisiologia , Neoplasias Ovarianas/patologia , Quercetina/farmacologia , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/fisiologia , Autofagia/fisiologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Quercetina/uso terapêutico , RNA Interferente Pequeno/genética , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Organismos Livres de Patógenos Específicos , Ácido Tauroquenodesoxicólico/farmacologia , Ensaio Tumoral de Célula-Tronco , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Chem Commun (Camb) ; 52(2): 251-63, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26561921

RESUMO

Some physicochemical intrigues for which transient electrochemistry was necessary to solve the problem are summarized in this feature article. First, we highlight the main constraints to be aware of to access to low time scales, and particularly focus on the effects of stray capacitances. Then, the electron transfer rate constant measured for redox molecules in a self-assembled monolayer configuration is compared to the conductance measured through the same systems, but at the single molecule level. This evidences strong conformational changes when molecules are trapped in the nanogap created between both electrodes. We also report about dendrimers, for which a short electrochemical perturbation induces creation of a diffusion layer within the molecule, allowing the electron hopping rate to be measured and analyzed in terms of molecular motions of the redox centers. Finally, we show that transient electrochemistry provides also useful information when coupled to other methodologies. For example, when an ultrasonic field drives very fast movements of a bubble situated above the electrode surface, the motion can be detected indirectly through a modification of the diffusion flux. Another field concerns pulse radiolysis, and we describe how the reactivity (at the electrode or within the solution) of radicals created by a radiolytic pulse can be quantified, widening the possibilities of electrochemistry to operate in biological media.

15.
Eur Rev Med Pharmacol Sci ; 19(11): 2048-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26125268

RESUMO

OBJECTIVE: The aim of this study is to investigate the feasibility and efficiency of Bone Morphogenetic Protein-2 (BMP-2) in regulating in vitro osteogenic differentiation of mouse adipose derived stem cells (ADSCs). MATERIALS AND METHODS: Mouse ADSCs were isolated from adipose tissues of C57/BL6 mice (age of 4-6 w) and cultured. Surface antigens of passage 3 (P3) ADSCs, including CD31, CD34, CD90, CD105 and CD133, were analyzed using flow cytometry. Overexpression of BMP-2 was achieved through gene transfection of ADSCs. In vitro osteogenic differentiation of transfected and non-transfected ADSCs cultured in specific induction media was evaluated by Alizarin Red staining. In addition, expression of osteoblast-specific gene, Runx2, was analyzed by quantitative RT-PCR (qRT-PCR). RESULTS: Abundant ADSCs could be isolated from adipose tissue. P3 ADSCs expressed stem cell-specific molecular markers, CD90 and CD105 but did not express CD31, CD34 or CD133. BMP-2 could efficiently transfect mouse ADSCs. Alizarin Red staining revealed that more calcified nodules were formed in BMP-2 transfected ADSCs. qRT-PCR further confirmed higher level of Runx2 expression in BMP-2 transfected ADSCs (p < 0.05). CONCLUSIONS: BMP-2 can promote in vitro osteogenic differentiation of mouse adipose stem cells.


Assuntos
Tecido Adiposo/citologia , Proteína Morfogenética Óssea 2/genética , Diferenciação Celular , Osteogênese , Células-Tronco/citologia , Transfecção , Animais , Antígenos CD , Sequência de Bases , Biomarcadores , Proteína Morfogenética Óssea 2/metabolismo , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core , Primers do DNA , Citometria de Fluxo , Técnicas In Vitro , Camundongos , Osteoblastos/metabolismo
16.
Ultrasonics ; 54(7): 1991-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24924786

RESUMO

Nanocrystalline ZnO films with both C-axis vertical grown and inclined angled grown were sputter-deposited onto aluminium foils (50 µm thick) and characterised for using as flexible ultrasonic transducers. As-deposited C-axis grown ZnO films were annealed at different temperatures up to 600 °C to enhance film crystallinity and reduce film stress. The C-axis grown ZnO film on the Al foil were bonded onto steel plates, and the pulse-echo tests verified a good performance (with dominant longitudinal waves) of the ultrasonic transducers made from both as-deposited and post-annealed films. Inclined angled ZnO films on the Al foil glued onto steel plates generated mixed shear and longitudinal waves in the pulse-echo test.

17.
J Physiol ; 561(Pt 2): 637-46, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15375194

RESUMO

This investigation was designed to determine if suppression of testosterone alters the ventilatory response to carbon dioxide in the presence of high and low levels of oxygen. Eleven healthy male subjects completed a series of rebreathing trials during wakefulness, before and after treatment with a long-acting gonadotropin-releasing hormone agonist. Five subjects also completed studies during non-rapid eye movement (NREM) sleep. During wakefulness, subjects initially hyperventilated to reduce the partial pressure of carbon dioxide (P(ET,CO2)) below 25 Torr. Subjects then rebreathed from a bag containing a normocapnic (42 Torr), low (50 Torr) or high oxygen (140 Torr) gas mixture. During each trial P(ET,CO2) increased while oxygen was maintained at a constant level. The threshold of the ventilatory response to carbon dioxide was considered to be the point at which minute ventilation began to rise in a linear fashion as P(ET,CO2) increased. The slope of the ventilatory response above the threshold was used as a measure of sensitivity to carbon dioxide. During NREM sleep, hypocapnia was induced via nasal mechanical ventilation. Several trials were completed until the cessation of mechanical ventilation resulted in a central apnoea which demarcated the threshold of the ventilatory response to carbon dioxide. In response to treatment with leuprolide acetate, the threshold measured in wakefulness decreased during carbon dioxide rebreathing in the presence of low (41.05 +/- 0.77 versus 39.40 +/- 0.83 Torr; P = 0.01) and high (46.32 +/- 0.56 versus 44.78 +/- 0.83 Torr; P = 0.01) oxygen levels. An increase in sensitivity (4.82 +/- 0.61 versus 7.17 +/- 1.20 l min(-1) Torr(-1); P = 0.02) was also observed during rebreathing in the presence of high but not low oxygen levels. The increase in sensitivity was accompanied by an increase in carbon dioxide production. The findings observed during NREM sleep were similar to those observed during wakefulness, since the P(ET,CO2) that demarcated the threshold was decreased after leuprolide treatment (42.1 +/- 0.6 versus 39.6 +/- 0.6 Torr; P = 0.002). Additionally, the decrease in P(ET,CO2) required to induce an apnoea was greater after treatment with leuprolide (2.56 +/- 0.25 versus 4.06 +/- 0.29 Torr; P = 0.004). We conclude that suppression of testosterone decreases the threshold of the ventilatory response to carbon dioxide during both wakefulness and sleep.


Assuntos
Dióxido de Carbono/farmacologia , Leuprolida/farmacologia , Ventilação Pulmonar/efeitos dos fármacos , Adulto , Análise de Variância , Humanos , Masculino , Ventilação Pulmonar/fisiologia , Sono/efeitos dos fármacos , Sono/fisiologia , Vigília/efeitos dos fármacos , Vigília/fisiologia
18.
J Appl Physiol (1985) ; 94(1): 101-7, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12391093

RESUMO

The hypocapnic apneic threshold (AT) is lower in women relative to men. To test the hypothesis that the gender difference in AT was due to testosterone, we determined the AT during non-rapid eye movement sleep in eight healthy, nonsnoring, premenopausal women before and after 10-12 days of transdermal testosterone. Hypocapnia was induced via nasal mechanical ventilation (MV) for 3 min with tidal volumes ranging from 175 to 215% above eupneic tidal volume and respiratory frequency matched to eupneic frequency. Cessation of MV resulted in hypocapnic central apnea or hypopnea depending on the magnitude of hypocapnia. Nadir minute ventilation as a percentage of control (%Ve) was plotted against the change in end-tidal CO(2) (Pet(CO(2))); %Ve was given a value of zero during central apnea. The AT was defined as the Pet(CO(2)) at which the apnea closest to the last hypopnea occurred; hypocapnic ventilatory response (HPVR) was defined as the slope of the linear regression Ve vs. Pet(CO(2)). Both the AT (39.5 +/- 2.9 vs. 42.1 +/- 3.0 Torr; P = 0.002) and HPVR (0.20 +/- 0.05 vs. 0.33 +/- 0.11%Ve/Torr; P = 0.016) increased with testosterone administration. We conclude that testosterone administration increases AT in premenopausal women, suggesting that the increased breathing instability during sleep in men is related to the presence of testosterone.


Assuntos
Hormônios Esteroides Gonadais/farmacologia , Caracteres Sexuais , Síndromes da Apneia do Sono/fisiopatologia , Fases do Sono/fisiologia , Testosterona/farmacologia , Administração Cutânea , Adulto , Dióxido de Carbono , Limiar Diferencial/efeitos dos fármacos , Feminino , Hormônios Esteroides Gonadais/administração & dosagem , Humanos , Hipocapnia/etiologia , Hipocapnia/fisiopatologia , Pressão Parcial , Respiração , Respiração Artificial , Testosterona/administração & dosagem , Volume de Ventilação Pulmonar
19.
Sheng Wu Gong Cheng Xue Bao ; 17(6): 683-7, 2001 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-11910765

RESUMO

Schemes for decolorization of broth and isolation of recombinant hirudin from the fermentation supernatants of recombinant yeast Pichia pastoris were developed to remove a great deal of non-desired proteins and coloring matters. Based on the stability of hirudin, heating is desirable to pre-treat the fermentation broth. Several different column chromatographies, including anion-exchange, cation-exchange, hydrokyapatite adsorption, hydrophobic interaction, gel filtration and their combination were investigated on the efficiencies of decolorization and isolation. Among these methods, the combination of cation-exchange and anion-exchange was found to be a success in both decolorization and isolation of hirudin.


Assuntos
Hirudinas/isolamento & purificação , Pichia/genética , Cromatografia em Gel/métodos , Cromatografia por Troca Iônica/métodos , Fermentação/fisiologia , Hirudinas/biossíntese , Hirudinas/genética , Temperatura Alta , Inibidores de Proteases/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
20.
Am J Physiol Lung Cell Mol Physiol ; 279(1): L136-42, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10893212

RESUMO

Loss of lung units due to pneumonectomy stimulates growth of the remaining lung. It is generally believed that regenerative lung growth involves only alveoli but not airways, a dissociated response termed "dysanaptic growth." We examined the structural response of respiratory bronchioles in immature dogs raised to maturity after right pneumonectomy. In another group of adult dogs, we also examined the effect of preventing mediastinal shift after right pneumonectomy on the response of respiratory bronchioles. In immature dogs after pneumonectomy, the volume of the remaining lung increased twofold, with no change in volume density, numerical density, or mean diameter of respiratory bronchiole, compared with that in the control lung. The number of respiratory bronchiole segments and branch points increased proportionally with lung volume. In adult dogs after pneumonectomy, prevention of mediastinal shift reduced lung strain at a given airway pressure, but lung expansion and regenerative growth of respiratory bronchiole were not eliminated. We conclude that postpneumonectomy lung growth is associated with proliferation of intra-acinar airways. The proportional growth of acinar airways and alveoli should optimize gas exchange of the regenerated lung by enhancing gas conductance and mixing efficiency within the acinus.


Assuntos
Brônquios/fisiopatologia , Regeneração/fisiologia , Animais , Peso Corporal , Brônquios/patologia , Broncografia , Cães , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Medidas de Volume Pulmonar , Masculino , Mediastino/diagnóstico por imagem , Pneumonectomia , Período Pós-Operatório , Radiografia Torácica
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